Question 19158
Substitute the value of x from the first equation into the second equation:


Value of x from the first equation is x=-3y + 10


-x + y = -10 becomes -(-3y+10) + y = -10


Solve for y: 
-(-3y+10) + y = -10
3y -10 + y = -10
4y = 0
y = 0


Go back and solve for x using either equation:


x = -3y + 10
x = -3(0) + 10
x = 10

So the solutions are y = 0 and x = 10.


Did I get it right?